Project Summary/Abstract Hazardous drinking among HIV-infected individuals is associated with serious health outcomes, including decreased adherence to antiretroviral therapy (ART) and decreased virologic suppression. The serious consequences of hazardous alcohol use for HIV infected individuals are often neglected in HIV health care settings. In many low resource settings, alcohol use is widely accepted and knowledge of potential risks is limited. In Vietnam, alcohol use is socially encouraged and hazardous drinking pervasive; over 20% of ART patients are hazardous drinkers. Injection drug users (IDU) comprise a large proportion of those infected with HIV in Vietnam and many are co-infected with HBV and HCV. Hazardous drinking is significantly associated with increased progression of liver disease among HIV-infected individuals co-infected with HBV and HCV, further underscoring the urgent need for effective alcohol reduction interventions in this context. We propose a three-arm randomized controlled trial to evaluate the comparative effectiveness and cost-effectiveness of two evidence-based interventions to reduce alcohol use among hazardous and heavy drinking HIV-infected ART clinic patients in Vietnam. Motivational Enhancement Therapy (MET) is a 4-session intervention that seeks to produce change through internally motivated change, while Cognitive Behavioral Therapy (CBT) is a more intensive, 12-session intervention that focuses on developing skills to manage triggers for alcohol. Using an innovative superiority-equivalency design, we will assess whether these two interventions result in better outcomes than an assessment-only control while simultaneously comparing the interventions against each other in terms of impact on patient-important outcomes and costs. Our primary outcomes will include abstinence from alcohol, HIV viral suppression, and incremental cost-effectiveness, all measured up to one year after starting each intervention.